Presentation on theme: "Learning how to Weld. Sit down and be quiet. Remember there is no such thing as a perfect weld."— Presentation transcript:
Learning how to Weld. Sit down and be quiet. Remember there is no such thing as a perfect weld.
Welding defined Arc welding is one of several fusion processes for joining metals. By applying intense heat, metal at the joint between two parts is melted and caused to intermix – directly, or more commonly, with an intermediate molten filler metal. Upon cooling and solidification, a metallurgical bond is created. The arc produces a temperature of about 6500 degrees F at the tip of the rod.
Safety Must wear welding helmet Must wear long sleeve shirt Must wear blue jeans or pants Must wear close toed shoes Must wear welding gloves (both hands) Safety glasses worn (under helmet)
Different types of welding OFWOxyfuel Gas Welding SMAWShielded Metal Arc Welding SAWSubmerged Arc Welding GMAWGas Metal Arc Welding (MIG) FCAWFlux Cored (Wire) Arc Welding GTAWGas Tungsten Arc Welding (TIG) PAWPlasma Arc Welding
Basic Knowledge Type of weld joints: T, Butt, Lap, Corner, and Edge Type of welds: Fillet weld or groove weld Fillet weld – A right triangle cross section of filler metal deposit joining two pieces of base material at or nearly perpendicular to each other. Groove weld – requires some base material prep work of at least a single bevel face.
Basic Knowledge Welding Positions: The main key of knowing welding positions is ask what is the weld face in? Below is a list of numeric then alpha meanings: – 1 stands for flat position – 2 stands for horizontal position – 3 stands for vertical position – 4 stands for overhead position – F stands for fillet weld – G stands for groove weld So if you are welding a vertical fillet weld, what numeric alpha position are we welding?
Basic Knowledge Answer is 3F This knowledge is found on blueprints in or near the welding symbols. More symbol reading will be covered in your next year classes.
Welding Positions Flat welds are either 1F or 1G Horizontal welds are either 2F or 2G Vertical welds are either 3F or 3G Overhead welds are either 4F or 4G
Welding Rods What does those numbers mean? The “E” stands for arc welding electrode First two represent the tensile strength – E60 is 60,000 lbs strength – E110 is 110,000 lbs strength
Welding Rods Next to last digit indicates position the electrode can be used in. 3 different positions exist: – 1 – is for use in all positions – 2 – is for flat and horizontal only – 3 – is for flat welding only Last digit represents AC, DC+ (reverse polarity) or DC- (straight polarity)
Welding Rods Here is a list of the numbers: – 0 DC+ electrode (reverse polarity) – 1 AC or DC- (straight polarity) – 2 AC or DC- – 3 AC, DC-, or DC+ – 4 AC, DC-, or DC+ – 5 DC+ – 6 AC or DC+ – 8 AC, DC-, or DC+
Welding Rods E6010 rod is used for all position in DC reverse and produces a deep penetrating weld, does not leave a superior weld appearance. E6011 rod is very similar to 6010, but can be used with AC or DC (both). E6013 rod can be used in AC & DC and produces a medium penetrating weld with superior weld appearance. E7018 rod is known as low hydrogen electrode in AC or DC (both). This electrode must be kept really dry, if allowed to get wet, you must dry it before using.
What is polarity? DC Straight – electrode is negative and the weld will have a faster melt off and deposit rate. The weld will have medium penetration. DC Reverse – electrode is positive and the weld penetration will be deep.
Welding Angle based on Positions The next slide will show you the different angle to hold the electrodes based on the welding position you are welding in.
How to setup Attach your ground clamp to the table or the work piece. Put the rod in the stinger Get gloves on, welding helmet down Move your rod down to the metal to strike
How to strike the Arc First, you will drag to start Do not stab Gently touch and drag Next, you will move back to start a puddle Puddle up before starting to move on
Actually Welding Now that you have your puddle going… Watch rod/metal relationship Watch speed of movement Most important watch your puddle
Running your puddle Here is a great shot of a running puddle Notice how you can see the path of welding
Review Wear proper safety equipment Lightly drag, do not stab Watch puddle, rod/metal relationship